Rolamite

ABSTRACT

Improvement features in &#39;&#39;&#39;&#39;rolamite&#39;&#39;&#39;&#39; type precision rolling suspension are taught, such a &#39;&#39;&#39;&#39;rolamite&#39;&#39;&#39;&#39; being known in the art as comprising cylindrical rollers held captive within a roller cage, between the S-shaped bends of a roller band therein. These features relate to &#39;&#39;&#39;&#39;double rolamites&#39;&#39;&#39;&#39; particularly involving two pairs of such rollers and especially &#39;&#39;&#39;&#39;linear rolamites&#39;&#39;&#39;&#39; adapted for unidirectional motion. Other features include arranging a plurality of rolamite/cage assemblies in a single operative combination; adapting a rolamite cage as part of an actuated load structure; arranging one, or several, &#39;&#39;&#39;&#39;drivemagnets&#39;&#39;&#39;&#39; along the roller-track of a rolamite assembly for prescribed magnetic attraction of the rollers and, thus, the magnetic incrementing thereof; and providing an array of detectcells along such a roller-track to monitor incremental movements of the band and roller assembly.

[ ROLAMITE [75] Inventor: Charles K. Wellington,

Nashua,

[52] US. Cl ..74/89.2 [51] ..Fl6h 27/02 [58] Field of Search ..74/89.2

[56] References Cited OTHER PUBLICATIONS D. F. Wilkes, Roalmite: A New Mechanical Design Concept, Sandia Laboratory, October 1967 Pages: 67,l24,l3l,133,132,143 and 176.

Primary Examiner-Charles J. Myhre Assistant Examiner-Wesley S. Ratliff, Jr. Attorney-Ronald T. Neiling and Fred Jacob ABSTRACT Improvement features in rolamite type precision rolling suspension are taught, such a rolamite being known in the art as comprising cylindrical rollers held captive within a roller cage, between the S-shaped bends of a roller band therein. These features relate to double rolamites particularly involving two pairs of such rollers and especially linear rolamites" adapted for unidirectional motion. Other features include arranging a plurality of rolamite/cage assemblies in a single operative combination; adapting a rolamite cage as part of an actuated load structure; arranging one, or several, drive-magnets" along the roller-track of a rolamite assembly for prescribed magnetic attraction of the rollers and, thus, the magnetic incrementing thereof; and providing an array of detect-cells along such a roller-track to monitor incremental movements of the band and roller assembly.

8 Claims, 10 Drawing Figures W BEARING HOUSING Patented May 1, 1973 3 Sheets-Sheet 1 w O J O m O O r-l.

FIG. IB

Illrll BEARING HOUSING INVENTOR CHARLES K. WELLINGTON Patented May 1, 1973 3 Sheets-Sheet 2 ATTORNEY RoLAMrrE This is a division of the Parent application Serial No. 728,250, filed May 10, I968 now abandoned.

BACKGROUND, NOVEL FEATURES By way of introductory discussion of the rolamite concept as known in the art, reference will be made to FIG. 1, in a schematic, illustrative rolamite assembly R,

where a pair of upper and lower cylindrical rollers r-u, r-l, respectively, are indicated as freely suspended, but captured, within the S-bends" of a prescribed rolamite band B, such as a thin, flexible steel web. These rollers are of regular circular cross-section and approximately the same diameter (though the diamete'rs may be different) and, besides being trapped in band B, are contained within a cage structure C comprising a top and bottom guide C-t, C-b respectively kept in fixed parallel relation by a pair of end-spacers C-S, C-S'. The rollers are disposed with their centerline at a prescribed inclination (angle a with respect to the rolling direction; see arrows). A mutual contact point C is established between the band and both rollers; while individual contact points of the rollers (to cage C) defines, with C, a contact line at contact angle b with the rolling direction.

Workers in the art will recognize this as a rather familiar rolamite construction and a very general showing thereof where, because of its pure rolling action, the device has very low resistance to motion and involves little wear. In general, such a rolamite needs no lubrication (except for some designs requiring ultralow friction). The band, the rollers, and/or the top or bottom guides may be modified, as known in the art, to generate force functions" of many different types such as might be useful for providing a return force, a detenting motion, variable spring action, a sequencing, etc. Such applications, as well as other features of this type rolamite, and others, may be found in a Wilkes Report (entitled Rolamites: A New Mechanical Design Concept" by B. F. Wilkes, 1322 Sandia Laboratory, AEC/Sandia Office of Industrial Cooperation No. SC-RR-67-656, October 1967). Workers in the art will recognize that rolamite structures are suitable for a wide range of applications and in general do not require precision tolerance machining to manufacture. Rolamites exhibit coefficients of friction on the order of b 1 to 10 percent of conventional bearings and no lubrication in the typical case. Further, special rolamite geometry can produce axial forces of any desired character and nearly all of the mechanical functions normally called for. Of course, another advantage of the rolamite is its simplicity involving as few as three or four piece-parts, constructable according to a simple modular design. in a wide range of miniaturized forms and wellsuited for mass production techniques.

Workers in the art will also understand that in a rolamite, resistance to motion is minimal and is usually the result of friction from microslip," from material deformation under contact pressure, and from hysteresis losses caused by the elastic flexing of the band. Some resistance might also result from variations in band thickness, or from irregularities in guide surfaces or roller surfaces. In general, it will be recognized that any rolamite involves the trapping of at least one pair of rollers between the S-bends of a rolamite band, as

shown in illustrative rolamite R, and that such a rollerpair/band configuration may be provided in general either according to a loose geometry arrangement (wherein the tension on the band is not particularly high and, for instance, the ends of the band are fixed, with pressure applied to the rolamite rollers by clamping between guides, such as in FIG. 6) or according to a tight geometry arrangement (whereby the ends of the band are pulled with considerable tension and there is no appreciable spacing gap between the band and rollers at the contact point). Perfect tight geometry c cannot ever be achieved, though it may be closely approached.

In a loose geometry rolamite, a very low rolling resistance is exhibited because the normal forces at the contact points are quite small. However, edge-guide means are, at times, provided to prevent the rollers from slipping out from within S-bends in the band. The tight geometry form is better adapted for precision mechanisms and has a minimum of backlash; however, it may exhibit more rolling resistance although, in some cases, the total resistance to motion may be less than that of the loose geometry (e.g., with its added sliding friction, etc., resulting from edge-guides not needed with tight geometry"). To approach a tight geometry and still keep band-tension relatively low, one may use bands having a relatively low value of stiffness. It will be apparent that, to keep the rollers within the band in a tight geometry configuration, it is relatively more critical that the S-bends define relatively perfect cylinders and that the roller-surfaces must, likewise, define relatively perfect, conforming cylinders. It is also important to keep the guide-surface (e.g., contact surfaces of C-t, C-b in FIG. 1) perfectly parallel and thereby maintain the band-mounting aligned so as to prevent band-twisting. These conditions also eliminate unbalanced wear (i.e., preferentially on one edge of the band or rollers) and this becomes increasingly critical as tension goes up. The precision requirements also become more critical as rolamite excursion distance increases since for small excursions, the rollers are far less likely to slip out of the band track, of course.

Another critical feature of tight geometry rolamites relates to surface anomalies and surface contaminants, such as dirt between the band and a roller or a guide. The tight geometry is greatly effected by variations in guide-spacing such as dirt particles, etc., which might cause band-crimp when the particles appear in a contact zone" such as between the rollers and the band. Such a crimp can act as a detent and, eventually, lead to band failure. Intruding dirt particles etc. can also increase rolling resistance and act as a wedge-stop. This problem can be reduced somewhat by using compressible materials, such as on the surface of the rollers or the guides, but this is usually undesirable because it increases rolling resistance.

Thus, it is a general object of the invention to provide the aforementioned and other features in improved linear rolamite arrangements. A related object is to provide such arrangements exhibiting greater versatility and multiple functions for cage and related roller elements, as well as effective magnetic roller translation. Another related object is to provide such characteristics in novel linear double rolamite arrangements, as described below; for instance, utilizing cage structures as actuator elements; employing multi-cage and multi-rolamite combinations; and using solenoid magnet incrementing means for roller translation.

A more particular object is to provide a double (roller pair) linear rolamite cage as a support for a translated load. A related object is to adapt such a cage for journalably suspending a reciprocatable load.

Another object is to provide a plurality of such cages both to function as such a load support and as such a suspension; especially for two-way load translation.

Yet another object is to provide such a rolamite cage with magnetic roller incrementing means along the path of band unfolding. A further object is to provide a plurality of such incrementing means along this path at intervals corresponding to successive respective rolleradvance increments. A related object is to provide such a cage together with one or more band-position detect stations arranged at prescribed detect axes along a band-unfolding path; each such station comprising a radiation sensor device adapted to respond to prescribed changes in light energy and to be covered by superposition of the band and rollers.

Other related objects, their features and advantages will be evident to those skilled in the art as the description of the following illustrative preferred embodiments proceeds, the particulars of these embodiments being described with relation to the following drawings, wherein like reference characters denote like elements:

FIG. I, a side elevation schematically indicating the rudiments of a rolamite combination by way of introduction to the invention;

FIGS. IA, 13, respectively a schematic plan view and a side elevation view of one double linear rolamite embodiment of the invention;

FIG. 2, a schematic plan view of a second embodiment similar to that in FIGS. 1A, 1B, but modified somewhat;

FIG. 3, an upper perspective view, somewhat schematic, of another multi-cage embodiment of the invention;

FIGS. 3A, 38, respectively indicating, schematically, an end elevation and a plan view ofa vertically stacked multi-cage embodiment, similar to that in FIG. 3, but modified somewhat;

FIG. 3C, a schematic plan view of embodiment similar to that in FIG. 2, but modified somewhat after the manner of the teaching in FIG. 3;

FIG. 4, a very schematic side elevation ofa rolamite similar to that in FIG. I, but in a somewhat modified embodiment including a schematically indicated magnetic roller-attracting arrangement; and

FIG. 5, an upper schematic, somewhat fragmentary, perspective of an embodiment like that in FIG. 4, but modified to indicate a plurality of magnetic incrementing devices, plus a plurality of motion-detect means.

INITIAL EMBODIMENTS The following double rolamite assembly embodiments (e.g., FIGS. 1A 3C). will be understood as generally involving reciprocating linear motion by trapping two pairs of rolamite rollers" within a rolamite band held within a rolamite cage (in the manner indicated above with respect to rolamite R in FIG. 1, except where otherwise noted) with one roller in each pair being rotatably suspended externally (e.g., its shaft in an outer bearing or other rolamite suspension, etc.). These double rolamite embodiments will further be understood as especially adapted for linear rolamite arrangements wherein the rolamite assembly (of cage) is intended to be unidirectionally translated (relatively pure linear motion, only in one dimension), especially over long displacements. Workers in the arts of providing translating elements for data processing apparatus (e.g., magnetic head positioners for Disc File) will recognize the importance of this function and the difficulty of producing it. These embodiments will teach how double linear rolamite arrangements according to the invention can solve these and related problems.

Thus, in FIGS. 1A, 113 there is schematically indicated a double linear rolamite assembly embodiment A-l suspended from a fixed frame (i.e., on shafts 8-1 from a set of bearings, Bg, Hg and on shaft 8-1 from fixed motor M) as known in the art. Embodiment A-l will be understood as thus suspended to be driven linearly (arrow) by a generally indicated motor means M of known construction. Rolamite A-l will be understood as double," i.e., employing two rolamite roller-pairs, Rl-l, Rl-l (as opposed to a single rolamite where one such rolamite-pair may be used, such as where the loading is light). The rollers will be large enough (in diameter) to accommodate sufficient space for the bearing and motor elements and provide the desired torque, rolling characteristics, etc., as known in the art. Rolamite assembly A-l also includes a band B-1 and cage C-l (like those in FIG. 1 except where noted). Cage C-l will be understood as reciprocatable linearly (arrow) and adapted to support a working load, such as the schematically-indicated magnetic head assembly HA (or, alternatively, other loads, such as a punched card translation means, etc.

especially loads functioning in computer peripheral devices). In each of these applications, a rolamite tracking unit, such as disclosed below relative to FIG. 5, may also be provided along the path of one of the rolamite assemblies so as to detect incremental roller motion and effect a very convenient, built-in, strobing. That is, when the rolamite band (B-l) moves to uncover (or cover) successive detect cells (e.g., along bottom-guide portion C-l-B of cage C-l) such strobe signals may be generated as known in the art. Of course, this mechanism may also be detented by means known in the art, such as by varying the top-bottom guide spacing (e.g., machining valleys into one or both guide-surfaces; providing cut-outs" in the band length, etc. see the Wilkes text, referred to above).

Rolamite assembly A 1 will, thus, be understood as a double (roller-pair) motor-driven type linear rolamite and will now be more particularly described. Assembly A-l is suspended for rolling motion on bearing shaft S- 1 fixedly attached to roller r-I in rolamite pair Rl-l to rotate therewith, while being journaled conventionally by a pair of outboard bearing assemblies Bg, Bg, these being spaced equidistantly outboard of cage C-1 and relatively centrally of its length so as to equalize moments. Alternatively, of course, a cantilevered suspension of cage C-l (from motor shaft S-l) may be used with only one such bearing; however, this wouldinvolve the risk of deflecting shafts S-1 and 8-1 (skewed to their original orientation), together with a possible misalignment of the rolamite rollers. Also, if motor shaft 8-] is not made stiff enough, a support bearing at its outboard end might also be required. Bearing operation will be optimized and long life assured if the bearing is designed so that its rotation is 360 or more with heavy loads. Thus, the rolamite roller-diameters should be set as small as is otherwise allowable (e.g., though not so small as to exceed acceptable limits of severe band-flexing or to overstress band B-l, etc.). A loose geometry might be used here, except where precision translation or high side loading" capacity is desired: in which cases, a tight geometry" will be preferable.

The construction of linear rolamite A-l in FIGS. 1A and 18 will now be particularized and exemplary materials and dimensions specified where significant, although workers in the art will recognize that the described features and advantages may be achieved with other equivalent means. Linear rolamite A-l as aforementioned generally comprises two pairs of rolamite rollers (RI-1, Rl-l') contained, with associated band 3-1 in rolamite cage C-l, with the opposite ends of band B-l attached at opposite ends of cage C-l such as to establish a prescribed amount of tension in B-l when roller pairs Rl-l, Rl-l' are trapped thereby, as illustrated. Rl-l, Rl-l each comprise a pair of rollers trapped in a respective S-bend portion of band B-l in a rather conventional rolamite fashion. Cage C-l is functionally somewhat equivalent to cage C in FIG. 1, comprising top and bottom guide pieces (C-l-t, C-l-b respectively), fixed in prescribed spaced, parallel relation by a pair of connecting endspacers. Of course, as aforementioned top guide portion C-l-t is adapted to support a load HA cantilevered out therefrom. Load HA is only generally indicating and comprises a known magnetic head assembly including a pair of opposed magnetic head transducers (h-l, h-2), arranged, as known in the art, to record-on, read-from, etc., respective adjacent magnetic disc tracks. Such tacks will be understood as accessed by controlled linear translation of rolamite A-l (cage C-l thereof) to register those heads with a selected track locus, as known in the art.

Generally, it will be preferred to fabricate cage C-l as a metal structure in a known manner (such as of hardened steel pieces welded together) to readily provide a rigid, load-supporting box. However, portions of the cage may be otherwise constructed (e.g., of molded plastic, etc. consistent with maintaining necessary structural strength, etc.). However, it will be apparent that it will usually be advantageous to construct the roller-contacting portions (i.e., the upper and lower roller-tracks" surfaces on C-ll, C-lb, respectively) to exhibit a hard flat surface (such as casehardened steel) and thereby prevent brinnelling, assure good flatness and minimize rolling-friction (contact with the rollers, and thus minimize stressing of the band, etc.).

Generally, rolamite band 8-1 will usually comprise a flexible strip of relatively hard, tough material, such as spring steel, berylium copper, or a conventional flat elastomeric belt. The band material may also, at times, be Mylar or a comparable plastic with a smooth surface for roller-contact. Of course, the band is made wide enough to accommodate the rollers (or a bit wider) long enough to accommodate the full roller excursion along the cage, and made thin enough to impart flexibility, yet toughness. Band B-l is fixedly attached (removably, if desired) at both of the inner extreme ends of the rolamite track along the cage top C-i-l or cage bottom C-l-b. Typically, a rolamite may be so simply and inexpensively constructed, that the entire unit, rather than individual elements, will be replaced in the event of part failure (except in cases of extreme precision manufacture and operation). It is not expected that in the usual case, one would want to remove and replace the rolamite band 13-1 or the cage or the rollers however, where desired this can readily be provided for.

The upper and lower rollers (r-u/r-l and r-u/r-I') of roller pairs Rl-l, Rl-l, respectively) should in general comprise rollers with a rather hard smooth surface and a regular cylindrical cross-section. They will have a diameter sufficiently large to minimize bending stresses on rolamite band B-l, yet not so large as to create space problems and limit bearing rotation (decrease bearing life). The roller diameters may be different, as with any rolamite. The rollers are trapped between their respective band-bends and they will be kept in prescribed offset adjacent, as indicated here, being unable to straighten up within cage C-1, and adapted to thereby effect the known rolamite action. These rollers will be understood as being constructed to be mechanically strong enough to bear the contemplated loads without deforming, etc. For instance, 0.875 in. diameter X 1.00 in. long rods of case-hardened steel (common pulley roller stock) or the like, will be satisfactory in a steel cage about 1.12 in. wide X 10.00 in. long X 1.75 in. high and a spring steel band about 15.00 in. long X 1.12 in. wide X 0.003 in. thick. Other materials may be used, of course, alone and together, consistent with providing adequate environmental characteristics (strength, corrosion resistance, etc.), compatible thermal characteristics (expansivity, etc.) as known in the art. For instance, in certain cases, such as when relatively light loads are expected and low rolling resistance is not a requirement and the intrusion of hard dirt particles is a problem, plastic roller surfaces (e.g., of polyurethane, l-lypalon, etc.) may be used.

Motor M may comprise any conventional drive means suitable for rotating the rolamite. Here, M is understood as including a drive shaft S-l, cantilevered out therefrom to be oscillated (rotated back and forth) at selectable times, developing a prescribed torque and adapted to carry the prescribed shaft load represented by rolamite A-l. Thus, drive shaft 8-1 is understood as pinned to roller r-l' (the lower roller of rolamite pair Rl-l') to drive it and support the associated load. Where necessary, an outboard bearing may be used as well.

Thus, it will be understood that when drive shaft 8-] is rotated a prescribed amount in a particular direction, roller r-l will be rotated accordingly, and cause the roller pair Rl-l to roll along band 8-1 in the associated direction (companion roller r-u being carried along). The other rolamite pair Rl-l will also be rolled in synchronism with the driving pair Rl-i, with driving roller r-l acting to pull band B-l about rollers r-l, r-u,

and thus rotate them together. Since there is no slip between the band and guide, the cage C-l accordingly moves along with the band.

A variant on the showing in FIGS. 1A, 1B is shown in FIG. 2 where a similar double linear rolamite embodiment A-2 is shown; however, here, the rolamite arrangement includes a cage C-2 which is fixed (not reciprocable, as with A-l while a bearing housing H- 2, is projected out from the rolamite assembly (carried by both roller pairs) and adapted to be reciprocated in the manner of cage C-l above. Rolamite arrangement A-2 may thus be understood as constructed and operating along the lines of rolamite A-l aforementioned except where noted, and includes rolamite cage C-2 together with an associated band B-2 and captured roller pairs Rl-2, Rl-2'. Here, the lower rollers (RZL, R-ZL) are affixed on respective shafts (8-2, 8-2, respectively,) to rotate therewith. Each shaft projects out to be journaled in a respective bearing portion in housing H-2, somewhat in the manner of embodiment A-l above. Alternatively, the upper rollers (R-Zu, R- 214) may be fixed on these shafts. With each shaft so journaled at its outer end in a conventional roller bearing assembly and with housing H-2 being carried by the rolamite shafts (journaled in the bearing assemblies in a conventional manner), rolamite A-2 will be understood as, itself, functioning as a following suspension-guide (following the housing). Housing H-2 will also be understood as preferably carrying a working load-arm L-2 (shown fragmentarily and understood as functionally comparable to head assembly HA in FIGS. 1A, 1B). The load on arm L-2 will thus be understood as being reciprocated linearly by any conventional drive means DM with rolamite A-2 providing a low-friction, translatable support-guide for the reciprocated housing-lead. Such a suspension is self-tracking, as well as exhibiting very low friction and eliminating conventional slide-guide elements (e.g., edge guides and engaging skid surfaces).

Of course, a number of rolamite arrangements, each like A-2, may be used in such a configuration rather than just one, such as by providing a similar rolamite and bearings on the other side of housing H-2, especially where heavy loads are involved. Moreover, housing H-2 may be designed and arranged to be supported somewhat differently from rolamite A-2, such as by straddling cage C-2 and with shafts 8-2, 8-2 extended symmetrically to also project on the other side of cage C-2, journaling them in respective bearings on housing H-2 and thus support the housing rather symmetrically from both sides as with a beam (e.g., like Cage 3-b between cages 3-a, 3-c in FIGS. 3A, 38). Such an arrangement would also help to minimize tilting" of the rolamite rollers and thus alleviate possible problems in tracking, in roller-skew, in roller ejection, etc. A load such as H-2 may obviously be reciprocated with many conventional drive means, such as electromagnetic actuators, mechanical eccentrics or with a linear motor" design arranging one of the armature tracks on housing H-2. The supported load (Is-2) in the foregoing embodiments may comprise a document picker, document translation means or the like, as well as a magnetic head positioner. The rolamite suspension will evidently provide these with a capability for long reliable displacements. Such mechanisms will exhibit a more positive drive characteristic than with the prior rolamite embodiment, since there is no real possibility of slip between the motor driven roller and the band (e.g., as is possible with embodiment A-Zl). Of course, workers in the art will recognize that the housing I-l-l and linear rolamite embodiment A-2 may be reversed, with the housing, instead, being mounted in a fixed frame and with the load L-2 projected from the cage of rolamite A-2 which, in turn, is adapted to be reciprocated by the drive DM, etc.

DESIGN CONSTRAINTS One important consideration in designing the foregoing double linear rolamites is load capacities. Now, load capacities are increased at the outset, by changing from a relatively conventional spherical bearing e.g., ball bearing) to a cylindrical one (rollers such as r-l, r-u in FIG. 1), due to reduction of contact stresses. Also, load capacity will, of course, vary directly with the roller diameter. The coefficient of rolling friction will vary inversely with this roller diameter. Hence, a relatively large diameter roller enhances both load carrying capability and reduces friction in the rolamite. Additionally, thev effects of perturbations -in element geometry, such as surface roughness (on the guide surfaces, or the roller-or band-contacting surfaces) will grow less significant as roller diameter increases.

Another design consideration is side load capabilities, preventing rollers and band from sliding out of a cage (in either geometry tight or loose). The side load capabilities of a rolamite can be improved with side guide means for the rollers, but this, of course, introduces sliding friction (drag on rollers and band along the cage track), the amount depending upon the depth of side guiding and materials used. Also a round cross-section belt may be used in company with a flat rolamite band to increase side load capacity, to reduce the movement of a cage relative rollers and band and to keep these aligned. Circular grooves (slots) in the rollers and the guide surfaces are provided as track seats for such a round belt and will supply thrust support. Here, the flat portion of a band would act as the required tension member to hold the rollers in the band. Also, an increase in the number of rolamites in a particular combination (that is along a single cage track) serves to increase side load capacity. Side loading can be prevented from contributing significantly to rolling friction in certain design configurations. The aforementioned Wilkes Report can provide details here.

Another design consideration relates to the dimensional and material characteristics of the rolamite band. In rolamite applications, such as for mounting reciprocating actuated devices in the computer arts, a long operating life is expected. Thus, the acceptable loading limits on a rolamite used here will be a function, primarily, of the fatigue limit of the band. The band is a critical element in the rolamite combination and thus the choice of band material must be made very carefully so as to optimize rolamite operation. Of course, the geometry tightness will set limits upon the performance of the band, since, as the tension in the band increases, the rolling friction and band stresses increase accordingly. It will always be desirable to minimize the normal forces in the contact zones (band roller guides) since these forces are largely responsible for the frictional losses in a rolamite pair. The flexural stiffness of the band will vary as its thickness (to the third power) and the maximum flexural stress for a given roller diameter will vary directly with band thickness. Thus, the ratio of band thickness to diameter (T/D) should always be kept as small as it is practicable. This will insure that friction and working flexural stresses are both minimized. Also, operating at the level of minimum working stress will minimize the tendency for stress relief under prolonged storage conditions, besides minimizing the effect of other failure mechanisms related to stress and contributing to maximum fatigue life of the element.

Perhaps the most important consideration in band selection, aside from frictional characteristics, are environmental characteristics. Corrosion prevention is particularly important, since a highly stressed band is more susceptible to corrosion than an unstressed one. Corrosion can be caused by contact of the band with dissimilar metals or by a corrosive ambient atmosphere in the operating environment of the rolamite and will reduce the fatigue life of the band and possibly contaminate the rolamite. A related environmental consideration is the differential thermal expansion (or contraction) resulting from the various materials and dimensions thereof used in the band element, the rollers and the guides. Temperature-induced variations in modulus of elasticity of the band material must also be considered. For proper operation, the band tension must be investigated at both extremes of the operating temperature range for the application. At these extremes, the band must not be overstressed, nor be so loose as to give unsatisfactory performance (e.g., allow the rollers to slip out). Band tension T and the maximum force Fm, (i.e., therefore function built into a rolamite for moving it under its own power) both depend upon the modulus of elasticity E. Therefore variations of E with temperature will also induce a shift in design parameters. Of course, the band may participate directly in producing a desired function. Therefore, other considerations such as the electrical, thermal and magnetic properties may enter into the selection of band material.

Another important design consideration relates to the rollers. The mass, the diameter, the load-bearing width, the modulus of elasticity, the surface hardness and the surface finish of the rollers must be selected carefully to be compatible with the contemplated conditions of maximum loading, of required inertia, and of acceptable frictional forces. The rollers often participate in the actuation of force functions produced by the rolamite assembly (e.g., as indicated in FIGS. 4 and 5). Therefore, other properties such as magnetic and electrical properties must also be considered also. Further, the roller surface materials should be compatible with the band material so that the two may act in proper contacting cooperation. For example, it is preferable to make either the band or roller surfaces slightly compressible (to take up dimensional tolerances, capture the rollers tightly, etc.) but great care must be taken that this does not cause excess drag and friction. For a positive retention of the roller within the S-bends of the band, it may be attached to the band in some manner such as with screws or rivets. However,

roller movement will be, of course, limited by any such fastening.

Another important design consideration relates to the guide elements selected. It will be apparent that the guide surfaces (e.g., the band-contacting surfaces of upper and lower guides C-T, C-B in FIG. 1) can be subjected to high concentrated loads resulting from normal contact forces. The guide surface material must be chosen so that no substantial or permanent surface is produced, such as a brinelling or the like. The guide surface must be compatible with the band material and since it may participate in producing functions, etc., its electrical, magnetic and other properties may also have to be considered, of course. The quality of the guide surfaces should be such as to prevent any undesired detents" due to roughness or non-uniformities therein. Also, surface hardness should be maximized to minimize rolling friction. Also, the guides should be stiff enough to limit their deflection under normal contacting forces; (e.g., it will be evident that a bow in a guide surface can cause an undesired detent, or bias force, on the rolamite.) For example, a guide surface would normally exhibit a maximum deflection at the center of its span and thus induce a rolamite to seek this as a rest position along the cage-track, corresponding to the position ofleast potential energy).

Another important design consideration relates to frictional forces. After a rolamite device is first assembled and as it is first operated, its rolling friction exhibited will decrease with use until a relatively constant value obtains. That is, the rolamite contact surfaces will wear-in and mate better after an initial wear-in" period, since one may assume that the same points are always making contact (ignoring any slip). A significant characteristic of a Rolamite design is that,.unlike a belt drive, slip and creep factors can be eliminated within design limits. Creep should definitely not appear if tension is kept uniform throughout the band. Also, the contact points help to hold the band on a given roller and thus enhance the arc of contact (i.e., the wetting-length of band or roller) and minimizes risk of slip. It is believed that the maximum friction torque on a top roller, such as roller r-u in FIG. 1, is given by the expression:

where T band tension S side spacing. less the band thickness ,u coeff. of friction d= roller diameter A rolamite roller spacing It was found experimentally that application of graphite, molybdenum disulfide or the like can decrease the coefficient of friction (applied along the inside of the band by two or three times or wherever contact exists).

MULTIPLE CAGES According to another feature, it has been found that a plurality of double linear rolamites may be arranged in operative combination as a multi-cage combination, the rolamites working together as a unit. For instance, a multi-cage embodiment A-3 is shown in FIG. 3 comprising three rolamite assemblies, each like the aforedescribed linear, double rolamites, i.e., comprising a pair of fixed assemblies (cages C-3a, C-3c) and an intermediate relatively movable assembly (cage C-3b), free for linear reciprocation. Movable cage C-3b includes rolamite elements adapted to be suspended in a low-friction, translatable guided manner by the fixedcage rolamites as indicated. In this multi-cage array, each rolamite will be understood as constructed and operating like the aforedescribed embodiments, except where noted. Thus, it will be understood that in general, this combination operates so that when the movable rolamite cage C-3b is translated linearly (direction of arrow D-3), the two associated roller pairs in C-3b(i.e., pairs Ill-3b, R1-3b' together with their associated band B-3b) will be rolled within cage C-Sb, with the upper roller in each pair, in turn, rotating its associated shaft (8-3, -3 respectively). Each shaft rotates, in turn, to operate the two outboard supporting roller pairs to which it is pinned (i.e., pair Rl-3a and pair Rl-3c on shaft S-3; pairs Rl-3c and 121-130 for shaft 5-3) so that an aligned trio of roller pairs mounted on a common shaft will roll back and forth in synchronism, each outer pair of rollers acting (along their respective cage tracks) to provide a guided, lowfriction journaling of the intermediate roller pair.

It has been found, however, that certain conventions must be observed in providing such multi-cage arrangements. Thus, either the conventions noted below in Example A below will obtain; or, alternatively, those in Example B (referring to embodiment A-3 in FIG. 3, exemplarity):

EXAMPLE A The coupling shafts (e.g., 5-3, 5-3 in embodiment A- 3) must connect opposite rollers, that is, connect an upper roller in the central rolamite to a lower roller in the outboard rolamites, or vice versa. Also, the angle of repose ((1, defined as the angle between roller center-lines and the plane of the roller track also shown in FIG. 1 above) of the middle roller-pairs must have the opposite polarity to that (repose angle) of the outboard roller pairs (i.e., same angle, opposite side of the vertical, or plumb"). Further, the middle rolamite band (of the middle cage) must wrap its rollers in the opposite direction to the wrapping sense of the outer bands (i.e., bands in the stationary outer cages).

EXAMPLE B As in Example A, where one connects coupling shafts to opposite rollers (lower to upper, as before); he may, however, alternatively modify the other two conventions, i.e., whereby the angles of repose (a) of connected roller pairs may be in the same direction; while the respective bands (in connected roller pairs) are also wrapped (about their rollers) in the same sense (wrapping direction),

One advantage to these multi-cage arrangements (e.g., as opposed to those in FIGS. 1A, 1B and other more conventional arrangements using bearings, etc.) is the elimination of bearings and their associated mechanisms, operating problems, expense, etc.; as well as the minimizing of resistance to motion. Another characteristic observed is that the displacement of the middle cage (e.g., C-3b, arrow D-3) will be twice the displacement of either fixed supporting roller-pair (e.g.. double that of Rl-3c). This will be advantageous in certain cases because the cages will then not need to be as long as would be the case in more conventional arrangements. For equal displacements, the cage in this mechanism need only be one-half the length of other rolamite cages (e.g., these not, themselves, supported by rolamites).

Such multiple cage linear rolamite arrangements may be driven (reciprocated linearly) in any conventional manner, such as before mentioned. They may be employed to reciprocate loads such as found in data handling devices in the computer arts, e.g., reciprocating elements in document translators, in magnetic head positioners (e.g., associated with disc pack drives), etc. The mechanisms according to these features should exhibit a more positive drive characteristic (e.g., than that of FIG. 1A). As before, suitable strobing and detenting techniques may also be conveniently applied here.

Also, alternative to the foregoing, the moving rolamite cage (C-3b) may be driven with a conventional motor and pulley arrangement driving one of the rolamite shafts (S-3 or 8-3) (and similarly with prior embodiments). Of course, with the rolamite shafts moving, a tensioning idler would also be used with this pulley to compensate for changing shaft-motor distances. Such multi-cage linear rolamite arrangements may be adapted to support and journal almost any function device relative to a work station or vice versa. For instance, another multi-cage linear rolamite array may be mounted atop cage C-3b as indicated in the alternate embodiment in FIGS. 3A, 33. That is, an upper multi-cage rolamite array AA3 may be mounted on lower array A-3. This variant on the embodiment shown in FIG. 3, whereby a plurality of multirolamites may be used to effect two-dimensional linear reciprocation such as will be seen to have many applications. Such a vertical stacking of a pair of linear rolamites might be used for two-dimensional translation of such loads as a print head, a marking head in a printer, or an X-Y Plotter. Alternatively, it could be used to translate a document reading head in two dimensions. Thus, in this embodiment, the upper rolamite array AA-3 comprises a pair of outer-supporting rolamite cages C-30a, C-30c, schematically depicted as fixed on lower moving cage C-3b.

Thus, in this embodiment, the upper rolamite array AA-3 comprises a pair of outer supporting rolamite cages C-30A, C-30C, schematically depicted as fixed on lower moving cage C-3b at the midpoint of their lower guide piece adjacent either respective end of C- 3b with a pair of rolamite shafts S-30, S-30 connecting opposed registering (upper or lower) pairs of rolamite rollers being affixed thereto for movable journaling therein and adapted to be driven by respective rollers in an intermediate rolamite cage C-30B (in the manner that cage C-3b is supported between cages C-3a, C-3c as aforementioned). Cage C-30B is thus adapted to be linearly reciprocated relative to outer cages C-30A, C- 30C, that is, in direction D-30B (arrow or east-west) by any conventional drive means in the manner aforementioned. Of course, the whole rolamite array AA-3 being mounted atop movable cage C-3b in the lower array A-3, will also be translated in the same direction as C-3b (that is, "north-south) orthogonal to D-30B. Workers in the art will appreciate other similar techniques for stacking such multi-cage rolamite arrays.

Another variance on the multi-cage embodiment of FIG. 3 is indicated in FIG. 3C wherein a pair of rolamite cages C-31, C-33 may be used to effect opposed reciprocating linear motions" (directions D-3l, D-33 respectively). That is, these two rolamite assemblies will be understood as intended for opposed synchronous reciprocation mutually, whereby both cages may be oppositely translated in synchronism, such as by motor M-3, the motor in this case serving to thrust one of the cagesin a particular direction (as understood with embodiment A-l in FIGS. 1A, 1B, for instance) while the motion of this cage and an associated rolamite pair therein responsively drives the other rolamite cage in the opposite direction. A drive shaft S- 30 is coupled to motor M-3 conventionally and serves to couple it to rotate one of the rollers in one of the two rolamite pairs in cage C-33, as in the foregoing embodiment A-I. A corresponding (e.g., upper) roller in the other pair (within cage C-33) is in turn coupled to rotate the second associated shaft 8-30 which, in turn, is journaled at its outer ends (for free rotation) in a pair of fixed bearing assemblies Bg-3, Bg-3, as with embodiment A-l above. Now, if, additionally, these shafts are each coupled to a respective roller in a respective roller pair in companion cage C-3l, according to the teachings in the preceding embodiments (cf FIG. 3 and Example A, for instance), it will be understood that a rotation of shaft -30 by motor M-3 so as to move cage C-33 in one direction (e.g., D-33) will simultaneously move the companion cage C-31 in the opposite direction (an equal distance in direction D-3l) in perfect synchronism. Of course, these cages may also be coupled to be reciprocated in the same (rather than in opposite) direction, if otherwise designed (i.e., other than Examples A or B). Workers in the computer peripheral arts will recognize that such a mechanism have advantageous applications, such as in a synchronous double-action document picker or in a document-translating mechanism having elements activated in opposed, synchronous fashion. Additionally, if the cages are kept close together, then the overall mechanism can be self-balancing (counter balanced) to a great extent.

MAGNETIC TRANSLATION According to another feature, a rolamite roller pair may be arranged to be incrementally translated by magnets arranged along the associated rolamite track, such as indicated in FIGS. 4 and 5. More particularly, with reference to FIG. 4, a rolamite embodiment A-4 is indicated and may be understood as being similar in construction to the aforedescribed embodiments ex cept as noted hereafter. Thus, embodiment A-4 includes a rolamite cage C-4, a band B-4 and a pair Rl-4 of rolamite rollers, r-4u, r-4l, adapted to be made and operated generally like the foregoing embodiments. However, as rather schematically indicated in this embodiment, magnetic means for translating the rolamite pair is also provided in the form of an electromagnet em including a selectively energizeable solenoid (cf leads LL for applying current pulses) which is arranged with its attracting pole face em-f along, or slightly below, the plane of the rolamite track (that is, the

plane tangent to that occupied by band 8-4 when it is unrolled (flat) over the locus of magnet em this being also apparent from the perspective showing of a modified arrangement in FIG. 5

It will be apparent that if the body of lower roller r- 41 is made sufficiently ferromagnetic (the band and other roller also magnetic, if necessary) and if sufficient flux is projected from magnet em, then assuming roller r-4l is at the illustrated reference (start) location (a prescribed gap distance from em-f), then sufficient attractive electromagnetic flux will be understood as projected from face em-f to attract magnetic roller r-41 toward pole face em-f (flux shown by aoorws to pull the roller thus and thereby close the air gapbetween them).

Although this air gap is usually small, the resultant linear displacement is typically not significantly affected by gap dimensions where it would be using prior art arrangements (e.g., an attracting end-magnet em The rolamite will thus be magnetically translated until the lower roller r-41 is centered over magnet pole face em-f (the position of minimum potential magnetic energy). An important feature is that, unlike prior art magnetic actuating means, the magnet is arranged so as to be passed-over by the attracted lead-element (i.e., it is disposed along the track of the rolamite rollers to be passed-over by them). For instance, a conventional disposition of the magnet would be as an end magnet" (at the position indicated in phantom at em; that is adjacent to, or slightly behind, one of the end spacers in cage C-4). In such a case the attracting (actuating) force would vary exponentially with gap size (according to the inverse square law of magnetic attraction). By contrast, the arrangement of a track magnet like em according to this feature is such as to provide a more constant (though not necessarily more efficient) attractive force and displacement velocity, as well as being much less limited by air gap size. Of course, a force function can be designed into this rolamite for returning the roller to its initial position (e.g., the reference position shown in FIG. 4) after the electromagnetic em has been de-energized; or alternatively for thrusting the roller further in the attracting direction (perhaps to be, next, attracted by a succeeding downstream magnet, such as in the fashion of the arrangement of FIG. 5). Mechanical detenting arrangements like this are indicated in the aforementioned report by Wilkes which also indicates more conventional exemplary rolamites and magnetic arrangements for detenting rolamite rollers. One might say, in other words, that an electromagnet arranged like track magnet" em in FIG. 4 acts in the fashion of a magnetic detent"; producing somewhat the same effect as a depression in the track or lower guide surface.

FIG. 5 indicates a variant on the teaching in FIG. 4 whereby an exemplary multi-magnet embodiment A-5 is (rather schematically) indicated. The rolamite in this embodiment (Rl5) will be understood as constructed and arranged like that in FIG. 4, except where otherwise indicated. Thus, A-5 includes a pair of rollers r-Su, r-5l trapped in a rolamite band 8-5, which is, in turn, adapted to be laid along a prescribed (lower) roller/band track T-5, indicated in phantom. However, here the magnetic translating unit indicated in phantom. However, here the magnetic translating unit indicated in FIG. 4 has been duplicated a number of times along this track T-5 at successive incremental magnet-stations" therealong. At each such station is a solenoid magnet assembly (like em above) (em-1, etc.) adapted to be selectively energizeable in a known manner with respective pole faces presented along T-S. This magnet array will be understood as adapted to enable the associated roller pair Rl-S to be magnetically translated by one magnet, then by its neighbor magnet, and so forth, upon the application of a respective current pulse to each solenoid coil at the proper time as known in the art. If an infinite number of such magnets were closely mounted together along T-S, one would approach the function of a linear motor device. Such a device, often called a linear inductosyn motor, etc., would give uniform motion along T-S, but no de- 'tenting. Workers in the art will visualize related arrangements wherein such track magnets" cooperate with such linear rolamites.

It will be readily apparent to those skilled in the art that the principles of the present invention are applicable to other related types of suspensions for linear translated devices and that suspension arrangement such as those shown, or related ones, may be provided by equivalent rolamite arrangements to those in the illustrated embodiments such as arrangements according to the taught features of improved linear rolamite arrangements, such as actuated rolamite cages, multiple rolamite cages, track magnet arrangements for incrementing rolamite rollers magnetically, alone, or together in combination. Thus, while in accordance with the provisions of the statutes there have been illustrated and described the best forms of the invention known, it will be apparent to those skilled in the art that changes may be made in the forms of the apparatus disclosed without departing from the spirit of the invention as set forth in the appended claims and that in some cases certain features maybe used to advantage without a corresponding use of other features or by modification thereof.

Having now described the invention, what is claimed as new and for which it is desired to secure by Letters Patent is:

l. A rolamite assembly in combination with a bearing housing, said rolamite assembly comprising:

a first and second pair of rolamite rollers,

cage means for supporting said first and second pairs of rolamite rollers,

flexible band means having portions disposed between and partially encompassing adjacent rotatable members of each of said pairs of rolamite rollers, said band means affixed under tension in said cage means so as to be moveably disposed within said cage means,

a pair of shaft means, each being affixed to and rotatable with one rotatable member in said each pair of rolamite rollers, said pair of shaft means also affixed to and carrying said bearing housing,

translatable load means affixed to said bearing housing for linear movement along a load path,

actuation means for engaging said shaft means, said actuation means adapted to thrust said bearing housing along said load path, and

said shaft means in response to said actuation means driving said rolamite assembly such that said may rolamite assembly functions as a following suspension guide to said movement of said bearing housing.

2. The combination as defined in claim 1 wherein said actuation means includes a pair of journal means fixedly disposed and externally adjacent to said rolamite assembly, and

one of said journal means is coupled to a respective one of said shaft means for rotational driving of said shaft means.

3. The combination as defined in claim 2 wherein a first one of said shaft means is projected from a respective upper or lower roller of said first pair of rolamite rollers,

a second one of said shaft means is projected from an opposite, respective lower or upper roller of said second pair of rolamite rollers, and wherein the angle of repose of said first pair of rolamite rollers has opposite polarity to the angle of repose of said second pair of rolamite rollers.

4. The combination comprising:

a pair of fixed bearing assemblies,

first and second rolamite assemblies,

each rolamite assembly including two pairs of rolamite rollers, cage means for supporting said pairs of rolamite rollers, and flexible band means having portions disposed between and partially encompassing adjacent rotatable members of each of said pairs of said rolamite rollers,

a pair of shaft means, each affixed at one end to one rotatable member in each of said pair of rolamite rollers in said first rolamite assembly and at its other end to a corresponding associated rotatable member in each of said pair of rolamite rollers in said second rolamite assembly,

actuation means coupled to said first rolamite assembly and joumaled in another rotatable member in one of said pairs of rolamite rollers, said actuation means driving said another rotatable member in said first rolamite assembly, and

said shaft means in response to said driving of said another rotatable member rotating such that said first rolamite assembly is driven in a first direction and said second rolamite assembly is driven in a second direction.

5. The combination as defined in claim 4 wherein a first one of said pair of shaft means is projected from a respective upper or lower roller in a first of said pair of rolamite rollers in each of said first and second rolamite assemblies,

a second one of said pair of shaft means is projected from an opposite, respective lower or upper roller in a second of said pair of rolamite rollers in each of said first and second rolamite assemblies, and wherein the angle of repose of said first pair of rolamite rollers has an opposite polarity to the angle of repose of said second pair of rolamite rollers.

6. A multicage rolamite combination comprising:

fixed first and second outer rolamite assemblies,

a moveable third inner rolamite assembly,

each rolamite assembly including first and second pairs of rolamite rollers, cage means for supporting said first and second pairs of rolamite rollers, and flexible band means having portions disposed between and partially encompassing adjacent rotatable members of each of said pairs of rolamite rollers,

said cage means in said each rolamite assembly aligned in parallel,

first and second drive shafts,

a primary roller in each respective first rolamite roller pair in all assemblies being fixedly coupled to said first drive shaft common to all said first pair of rolamite rollers,

a secondary roller in each respective second roller pair in all assemblies being fixedly coupled to said second drive shaft common to all said second pair of rolamite rollers, said secondary rollers being opposite in order to said primary rollers such that they occupy an opposite upper or lower relationship in their pairs, and

said first and second fixed rolamite assemblies adapted to effectively support said moveable third rolamite assembly so as to provide for the suspension of said third rolamite assembly.

7. The combination as defined in claim 6 wherein the angle of repose of connected roller pairs in adjacent rolamite assemblies are disposed with the same polarity, and

said flexible band means in said each rolamite roller pairs in all rolamite assemblies are wrapped in the same wrapping direction.

8. The combination as defined in claim 6 wherein the angle of repose of connected roller pairs in adjacent rolamite assemblies are disposed with opposite polarity, and

said flexible band means in said each rolamite roller pairs in all rolamite assemblies are wrapped in opposite wrapping directions.

UNHED STATES PATENT CFFKCE CERWIFECA'EE Ct CCRRECHCN Patent No. 3 730,007 Dated Mag 1, 1973 Invencm-(s) Charles K. Wellington It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Cel 15, line 53, delete "twolmztte".a

131311 15, line 5 9, delete "tolamitem Colum 16, line 14, delete 1':oldnni'i:e'. Column 16, line '17, delete "rolamite".

Column 16, line 18, delete rolamite e Column 16, line 20, delete "rolamite". Column 16, line 25, delete "rolemiteW Column 16, line 26, delete "rolmnite". Column 16, line 29, delete "rolamite", Column 16, line 31, delete rolamite", Column 16, line 34, delete "rolamite". Column 16, line 38, delete "rolamite'.' Column 16, line 49, delete "rolamite". Column 16, line 53, delete "rolamite". Colum 16, line 56, delete "rolamite",

Column 16, line 58, delete "rolamite".

Column 16, line 63, delete "rolamite".

FORM PC4050 (10-69) USCOMM DC ear/maps;

us. covznuusm nmmm; ornc: was o-sss-saa, (a

UNITED STATES PATENT @FFKQE PAGE 2 @ERTlFlQATE @F QQREQTE Patent No. 3,730,007 Dated May 1 1973 Inventor(s) Charles K. Wellington I I It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col 16, line 64, delete "rolamite'i, Column 17, line 2, delete "rolamite". Gaol 17, line 7, delete rolaunite".,

Column v 17, line 10, delete "rolamite". Column 17, line 14, delete "rolamite". Column 18, line 8, delete "rolamite".

Column 18, line 15, delete "rolamite".

Signed and sealed this 5th day of February 1974.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. RENE D. TEGTMEYER Attesting Officer Acting Commissioner of Patents FORM PC4050 USCOMM-DC cows-ps9 US GOVERNMENT PRINTING OFFICE 2 i989 0-366-J8l, 

1. A rolamite assembly in combination with a bearing housing, said rolamite assembly comprising: a first and second pair of rolamite rollers, cage means for supporting said first and second pairs of rolamite rollers, flexible band means having portions disposed between and partially encompassing adjacent rotatable members of each of said pairs of rolamite rollers, said band means affixed under tension in said cage means so as to be moveably disposed within said cage means, a pair of shaft means, each being affixed to and rotatable with one rotatable member in said each pair of rolamite rollers, said pair of shaft means also affixed to and carrying said bearing housing, translatable load means affixed to said bearing housing for linear movement along a load path, actuation means for engaging said shaft means, said actuation means adapted to thrust said bearing housing along said load path, and said shaft means in response to said actuation means driving said rolamite assembly such that said rolamite assembly functions as a following suspension guide to said movement of said bearing housing.
 2. The combination as defined in claim 1 wherein said actuation means includes a pair of journal means fixedly disposed and externally adjacent to said rolamite assembly, and one of said journal means is coupled to a respective one of said shaft means for rotational driving of said shaft means.
 3. The combination as defined in claim 2 wherein a first one of said shaft means is projected from a respective upper or lower roller of said first pair of rolamite rollers, a second one of said shaft means is projected from an opposite, respective lower or upper roller of said second pair of rolamite rollers, and wherein the angle of repose of said first pair of rolamite rollers has opposite polarity to the angle of repose of said second pair of rolamite rollers.
 4. The combination comprising: a pair of fixed bearing assemblies, first and second rolamite assemblies, each rolamite assembly including two pairs of rolamite rollers, cage means for supporting said pairs of rolamite rollers, and flexible band means having portions disposed between and partially encompassing adjacent rotatable members of each of said pairs of said rolamite rollers, a pair of shaft means, each affixed at one end to one rotatable member in each of said pair of rolamite rollers in said first rolamite assembly and at its other end to a corresponding associated rotatable member in each of said pair of rolamite rollers in said second rolamite assembly, actuation means coupled to said first rolamite assembly and journaled in another rotatable member in one of said pairs of rolamite rollers, said actuation means driving said another rotatable member in said first rolamite assembly, and said shaft means in response to said driving of said another rotatable member rotating such that said first rolamite assembly is driven in a first direction and said second rolamite assembly is driven in a second direction.
 5. The combination as defined iN claim 4 wherein a first one of said pair of shaft means is projected from a respective upper or lower roller in a first of said pair of rolamite rollers in each of said first and second rolamite assemblies, a second one of said pair of shaft means is projected from an opposite, respective lower or upper roller in a second of said pair of rolamite rollers in each of said first and second rolamite assemblies, and wherein the angle of repose of said first pair of rolamite rollers has an opposite polarity to the angle of repose of said second pair of rolamite rollers.
 6. A multicage rolamite combination comprising: fixed first and second outer rolamite assemblies, a moveable third inner rolamite assembly, each rolamite assembly including first and second pairs of rolamite rollers, cage means for supporting said first and second pairs of rolamite rollers, and flexible band means having portions disposed between and partially encompassing adjacent rotatable members of each of said pairs of rolamite rollers, said cage means in said each rolamite assembly aligned in parallel, first and second drive shafts, a primary roller in each respective first rolamite roller pair in all assemblies being fixedly coupled to said first drive shaft common to all said first pair of rolamite rollers, a secondary roller in each respective second roller pair in all assemblies being fixedly coupled to said second drive shaft common to all said second pair of rolamite rollers, said secondary rollers being opposite in order to said primary rollers such that they occupy an opposite upper or lower relationship in their pairs, and said first and second fixed rolamite assemblies adapted to effectively support said moveable third rolamite assembly so as to provide for the suspension of said third rolamite assembly.
 7. The combination as defined in claim 6 wherein the angle of repose of connected roller pairs in adjacent rolamite assemblies are disposed with the same polarity, and said flexible band means in said each rolamite roller pairs in all rolamite assemblies are wrapped in the same wrapping direction.
 8. The combination as defined in claim 6 wherein the angle of repose of connected roller pairs in adjacent rolamite assemblies are disposed with opposite polarity, and said flexible band means in said each rolamite roller pairs in all rolamite assemblies are wrapped in opposite wrapping directions. 